1. Field of the Invention.
This invention relates to devices and systems that are used to form radial drain holes relative to a generally vertical oil or gas well hole. The new system and method includes a tube bending tool lowered into a well casing to the desired depth to create radial drain holes. Hydraulic fluid tubing is then passed through the tool to direct the hydraulic fluid tubing or piston in a radial direction for use of hydraulic or jet fluid pressure to drill drain holes.
2. Description of Related Art.
Various devices, systems and methods have been disclosed in related art which may be used to form radial bore holes from an existing oil or gas well hole. These devices normally use rotary driven bits, cutting tools and the like to cut through the oil or gas bearing underground formation of interest. These systems essentially use motor driven mechanical cutting blades, bits and the like to form a borehole.
There are also hydraulic fluid or jet pressure drilling systems for creating boreholes. An example of such a system is that disclosed in U.S. Pat. No. 4,527,639, Issued Jul. 9, 1985. This invention includes use of hydraulic fluid pressure to drill both vertical and horizontal bore holes. The disclosures include a whipstock for bending a piston/drilling tube having a head for directing the pressurized cutting fluid. When the bore hole has been created the tube remains in the bore hole to be used to introduce fluid, which may be at an elevated temperature, to create pressure in an oil or gas bearing formation to facilitate recovery of oil or gas through an existing well structure.
The present invention uses coiled hydraulic fluid tubing with a jet nozzle, at its forwarded end the combination also called a piston, to conduct cutting fluid under pressure to the desired location to create a borehole. The tubing is passed through a tube bending tool retained at a specified depth in an oil or gas well casing. The fluid pressure of the cutting fluid forces the tubing and jet nozzle into the underground formation thereby cutting or boring a drain hole radially from the existing well casing. The tube and jet nozzle are then extracted from the drain hole. The tube bending tool is then rotated in the well casing and tubing with jet spray is again used to form another radial drain hole using a new tube and jet spray. In this manner a plurality of drain holes may be formed radially from an existing well casing to extract oil or gas from underground formations that were not producing zones for the original well formation.
One object of the present invention is recovery of oil or gas from zones of underground formations, which were not tapped or were bypassed when the original well was formed in favor of much larger production formations. Another object is an improved tube bending tool for use with hydraulic fluid tubing. A further object is an improved method of producing a plurality of radial bore or drain holes emanating from an existing well casing.
In accordance with the description presented herein, other objectives of this invention will become apparent when the description and drawings are reviewed.